1. Field of the Invention
This invention pertains to the art of gas turbine combustors, particularly those of the catalytic reactor type.
2. Description of the Prior Art
The most common arrangement for combustion of air-fuel mixtures for use in gas turbines has been the conventional combination of fuel, oxygen and spark. Sometimes exhaust gas burning is also used to provide reheat for further use or to reduce for disposal of the gases. In either case, the temperature during part of the process substantially exceeds the final temperature, which is an undesirable result as it produces noxious by-products. Also, there is a condition of non-uniformity of temperature often developed through the cross section of the combustor.
One proposed way of accomplishing combustion without overheating involves bringing the air-fuel mixture in contact with a catalyst which is coated on a ceramic substrate. While the substrate may take various forms, one proposed form is that of a honeycomb which, if it has its passage axes parallel to the direction of flow does not preclude a non-uniform temperature distribution downstream of the reactor caused by a non-uniform air-fuel mixture upsteam of the reactor. An EPA report No. 650/273-014 dated August 1973 and entitled "Investigation of Surface Combustion Concepts for NOX Control in Utility Boilers and Stationary Gas Turnbines" states that among the geometrically different configurations usable as catalyst supports in tail abatement systems there is included a cross flow-type structure that enhances flow turbulence and mixing.
U.S. Patent application Ser. No. 520,831 filed Nov. 4, 1974, and now abandoned, discloses one arrangement for a catalytic combustor for a gas turbine and also identifies a number of prior art U.S. patents relating to catalytic devices relating to gas turbines.
It is the aim of this invention to provide an improved catalytic combustor for a gas turbine.